Thermarest Backpacking Pads Z-Lite Sol Sleep Pad-Regular-Limon 6670. Both the Z Lite SOL and the original Z Lite feature a compact accordion-style shape and heat-trapping dimples. The Z Lite SOL adds our reflective ThermaCapture coating that helps capture radiant heat increasing overall warmth by nearly 20percent. The proprietary foams are softer on top for extra comfort and denser on the bottom for extra durability. Wherever you’re headed a Z Lite mattress is the right choice for ultralight warmth durability and comfort.